SQL 2005 行转列，列转行，未知行转列时使用动态sql

SQL 2005 行转列，列转行，未知行转列时使用动态sql。

Create TABLE salesByMonth ( year char(4), month char(3), amount money, PRIMARY KEY (year, month) ) 

Insert INTO salesByMonth (year, month, amount) VALUES('2004','Jan', 789.0000) 
Insert INTO salesByMonth (year, month, amount) VALUES('2004','Feb', 389.0000) 
Insert INTO salesByMonth (year, month, amount) VALUES('2004','Mar', 8867.0000) 
Insert INTO salesByMonth (year, month, amount) VALUES('2004','Apr', 778.0000) 
Insert INTO salesByMonth (year, month, amount) VALUES('2004','May', 78.0000) 
Insert INTO salesByMonth (year, month, amount) VALUES('2004','Jun', 9.0000) 
Insert INTO salesByMonth (year, month, amount) VALUES('2004','Jul', 987.0000) 
Insert INTO salesByMonth (year, month, amount) VALUES('2004','Aug', 866.0000) 
Insert INTO salesByMonth (year, month, amount) VALUES('2004','Sep', 7787.0000) 
Insert INTO salesByMonth (year, month, amount) VALUES('2004','Oct', 85576.0000) 
Insert INTO salesByMonth (year, month, amount) VALUES('2004','Nov', 855.0000) 


select Year,[Jan],[Feb],[Mar],[Apr],[May],[Jun],[Jul],[Aug],[Sep],[Oct],[Nov] 
FROM salesByMonth 
PIVOT ( sum(amount) FOR month IN ([Jan],[Feb],[Mar],[Apr],[May],[Jun],[Jul],[Aug],[Sep],[Oct],[Nov]) ) AS ourPivot ORDER BY Year


--动态sql写法
declare @sql varchar(8000)
select @sql = isnull(@sql + '],[' , '') + month from salesByMonth group by month
set @sql = '[' + @sql + ']'
exec ('select * from salesByMonth  pivot (sum(amount)  for month in (' + @sql + ')) AS ourPivot ORDER BY Year')


Create TABLE salesByMonth1 ( year char(4), Jan money,Feb money,Mar money,Apr money,
May money,Jun money,Jul money,Aug money,Sep money,Oct money,Nov money, amount money) 


Insert INTO salesByMonth1 (year,[Jan],[Feb],[Mar],[Apr],[May],[Jun],[Jul],[Aug],[Sep],[Oct],[Nov]) 
VALUES('2005',789.00,389.00,8867.00,778.00,78.00,9.00,987.00,866.00,7787.00,85576.00,855.00)
Insert INTO salesByMonth1 (year,[Jan],[Feb],[Mar],[Apr],[May],[Jun],[Jul],[Aug],[Sep],[Oct],[Nov]) 
VALUES('2005',734.00,389.00,84367.00,378.00,734.00,9.00,47.00,866.00,7487.00,8536.00,83.00)
select * from salesByMonth1


select Year,需要转的列名,需要转的列值
FROM salesByMonth1 
UNPIVOT (需要转的列值 FOR 需要转的列名 IN (Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov) ) AS ourPivot ORDER BY Year


--动态sql写法
declare @sql varchar(8000)
set @sql = 'Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov'
exec ('select Year,需要转的列名,需要转的列值 FROM salesByMonth1 UNPIVOT (需要转的列值 FOR 需要转的列名 IN ('
 + @sql + ')) AS ourPivot ORDER BY Year')